The microSD Shield equips your Arduino with mass-storage capability, so you can use it for data logging or other projects. Communication with microSD cards is achieved over a Serial Peripheral Interface (SPI). The SCK, DI, and DO pins of the microSD socket are broken out to the ATmega168/328's standard SPI pins (digital 11-13), while the CS pin is broken out to Arduino's D8 pin. The Arduino 5V is converted to 3.3V signals in accordance with SD specifications.

If you decide to use one of the many open-source FAT libraries (e.g. FAT16 or SDFat), make sure to change the code to reflect the location of the CS pin. Most libraries assume the CS pin is connected to D10; this will have to be changed to D8. Also for the libraries to work, pin D10 will have to be set as an output in the setup() section of your sketch. The shield also includes a large prototyping area with a 13×12 grid at 0.1" pitch.

This shield comes populated with a microSD socket, red power indicator LED, and a reset button. It does not come with headers installed. See the options below for compatible connectors that you can use.